Comparing the clinical effectiveness of different new-born hearing screening strategies. A decision analysis

Background: Children with congenital hearing impairment benefit
from early detection and treatment. At present, no model exists
which explicitly quantifies the effectiveness of universal newborn
hearing screening (UNHS) versus other programme alternatives in
terms of early diagnosis. It has yet to be considered whether early
diagnosis (within the first few months) of hearing impairment is of
importance with regard to the further development of the child
compared with effects resulting from a later diagnosis. The
objective was to systematically compare two screening strategies
for the early detection of new-born hearing disorders, UNHS and
risk factor screening, with no systematic screening regarding their
influence on early diagnosis. Methods: Design: Clinical
effectiveness analysis using a Markov Model. Data Sources:
Systematic literature review, empirical data survey, and expert
opinion. Target Population: All newborn babies. Time scale: 6, 12
and 120 months. Perspective: Health care system. Compared
Strategies: UNHS, Risk factor screening (RS), no systematic
screening (NS). Outcome Measures: Quality weighted detected child
months (QCM). Results: UNHS detected 644 QCM up until the age of 6
months ( 72,2%). RS detected 393 child months (44,1%) and no
systematic screening 152 child months (17,0%). UNHS detected 74,3%
and 86,7% weighted child months at 12 and 120 months, RS 48,4% and
73,3%, NS 23,7% and 60,6%. At the age of 6 months UNHS identified
approximately 75% of all children born with hearing impairment, RS
50% and NS 25%. At the time of screening UNHS marked 10% of
screened healthy children for further testing ( false positives),
RS 2%. UNHS demonstrated higher effectiveness even under a wide
range of relevant parameters. The model was insensitive to test
parameters within the assumed range but results varied along the
prevalence of hearing impairment. Conclusion: We have shown that
UNHS is able to detect hearing impairment at an earlier age and
more accurately than selective RS. Further research should be
carried out to establish the effects of hearing loss on the quality
of life of an individual, its influence on school performance and
career achievement and the differences made by early fitting of a
hearing aid on these factors.